Evidence of hydrocarbon leakage has been well documented across the SW Barents Sea and is commonly associated with exhumation in the Cenozoic. While fault leakage is thought to be the most likely cause, other mechanisms are possible and should be considered. Further study is required to understand what specific mechanism(s) facilitate such leakage, and why this occurs in some locations and not others. In a case study of the Snøhvit Field, we use seismic and well data to quantify fault- and top-seal strength based on mechanical and capillary threshold pressure properties of fault and cap rocks. Magnitude and timing of fault slip are measured to acknowledge the role that faults play in controlling fluid flow over time. Results based on theoretical and in situ hydrocarbon column heights strongly indicate that across-fault and top-seal breach by capillary threshold pressure, and top-seal breach by mechanical failure are highly unlikely to have caused hydrocarbon leakage. Instead, top-seal breach caused by tectonic reactivation of identified faults is likely to have facilitated hydrocarbon leakage from structural traps. The results of this case study acknowledge the different mechanisms by which hydrocarbons can leak from a structural trap. Employing both a holistic and quantitative approach to assessing different seal capacities reduces the likelihood that a particular cause of hydrocarbon leakage is overlooked. This is particularly relevant for the Snøhvit Field in its dual capacity as a producing gas field and as a carbon sequestration site since both systems rely on a thorough understanding of seal capacity and leakage potential.

中文翻译：

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对西南巴伦支海哈默菲斯特盆地结构性圈闭的碳氢化合物滞留和泄漏的关键控制：对前景分析和风险评估的影响

在西南巴伦支海，碳氢化合物泄漏的证据已被很好地记录下来，并且通常与新生代的挖掘有关。虽然故障泄漏被认为是最可能的原因，但其他机制也是可能的，应该加以考虑。需要进一步研究以了解促进此类泄漏的具体机制，以及为什么会在某些位置而不是其他位置发生这种情况。在 Snøhvit 油田的案例研究中，我们使用地震和井数据根据断层和盖层的机械和毛细管阈值压力特性来量化断层和顶封强度。测量断层滑动的幅度和时间，以确认断层在控制流体流动方面所起的作用。基于理论和原位烃柱高度的结果强烈表明，毛细管阈值压力导致的跨断层和顶部密封破裂以及机械故障导致的顶部密封破裂极不可能导致油气泄漏。相反，由已识别断层的构造再激活引起的顶部密封破裂很可能促进了结构圈闭的碳氢化合物泄漏。本案例研究的结果承认了碳氢化合物从结构性圈闭中泄漏的不同机制。采用整体和定量的方法来评估不同的密封能力，可以减少忽视碳氢化合物泄漏的特定原因的可能性。